Method of estimating risk of dental decay, apparatus of estimating risk of dental decay, system of estimating risk of dental decay and program of estimating risk of dental decay

ABSTRACT

The present invention provides a method of evaluating the risk of possible caries and the device, system, and program of the same, which is useful for the subjects to keep their mouth conditions best by measuring the chemical properties of saliva samples collected from the mouths of subjects to allow for easy and sanitary evaluation of the risk of possible caries in a short time and to help the subjects accurately recognize their risk of possible caries and closely consult their dentist. In the present invention, saliva from the mouth of subject is collected, a given ratio of acid is added to the saliva, and the chemical property of the saliva is measured to evaluate the risk of possible caries base on the measured value.

TECHNICAL FIELD

The present invention relates to a method of accurately evaluating therisk of possible dental caries by measuring the chemical properties ofsamples collected from subjects such as saliva and the device, system,and program of the same and in particular to an evaluation of the riskof possible dental caries using saliva samples on a chemical propertymeasuring device capable of micro measurement and noninvasivemeasurement.

BACKGROUND ART

Conventionally, dentists have visually examined patients' mouths tocheck for any the dental caries in diagnosing their dental health. Thistype of dental health examination is, for example, done at every sixmonths. Then the examinee's mouth condition is kept better by easytreatment because every dental caries is detected before it becomes toneed complex treatment.

On the other hand, this method has a problem in that a variance amongindividuals can not be avoided in determining the resistivity of theirmouths to possible caries, namely the their risk of possible dentalcaries. For that reason, it is sufficient for some patients to undergomouth health examination at a longer interval, while it is required forother patients to do so at a shorter interval.

Moreover, in the case where a patient undergoes the examination byhis/her own dentist, the dentist can estimate the risk of possibledental caries to some extent from his/her examination history, though itis difficult for the dentist, even having many experiences, toaccurately determine such a risk in new patients only by visuallyexamining their mouths. Accordingly, in some cases, the dentist requeststhe patient to come again for re-examination in a short time, imposing aburden on the patient.

Furthermore, the patient, who requests the dentist to examine his/hermouth, need to undergo the correct treatment by him, though it isdifficult for him/her to well understand the need for treatment that thedentist determines to be indispensable. In this context, some patientsdiscontinue their treatment at the same time they obtain relief frompain even in midcourse of treatment and they tend to postpone theresumption of treatment if being requested by the dentist to come againbecause they can not easily detect any caries at the first stage in amirror.

Although the dentists suggest their patients the importance of keepingthe patients' mouth conditions better, it is difficult for them to givean advice to the patients on treating any invisible caries or removingthe risk of possible dental caries.

To address this situation, the caries risk test is commonly used usingsaliva samples collected from the patients' mouths for determiningwhether their mouth conditions are subject to caries.

FIG. 11 is a view explaining an example of a conventional caries risktest technique. First, as show in FIG. 11A, to collect a measurableamount of saliva, the subject 14 bites a paraffin pellet 90 and the likefor inducing the secretion of saliva.

Second, as show in FIG. 11B, the secreted saliva sample 15 is collectedinto a container 91, for example a beaker. Then, as shown in FIG. 11C,individually packed test strip 92, to which a drug for measuring theirpH buffer capacity has been applied, is taken out from the pack.

FIG. 11D is a view showing a procedure involving steps for sucking outthe collected saliva sample 15 using a pipette 93 and the like anddropping it on the pH buffer capacity measurement point 92 a with thedrug on the test strip 92 until all of them are wetted with the salivasample 15. As shown in FIG. 11E, after being left for five minutes, thecolor of the pH buffer capacity measurement point 92 a on the test strip92 wetted with the saliva sample 15 changes.

Finally, as shown in FIG. 11F, the changed color of the pH buffercapacity measurement point 92 a is compared with those displayed in aprepared color chart 94 to evaluate the risk of possible dental cariesbased on the collected saliva sample 15.

However, the conventional caries risk test technique has a problem inthat the subject 14 or a laboratory technician may come contact with thesaliva sample at a high provability because it involves the steps forcollecting a large amount of saliva sample 15 into the container 91 anddripping it on the strips 92 using the pipette 93 and the like, leadingto insanitation. Moreover, to collect a measurable amount of salivasample 15 into the container 91, the subject 14 needs to bite theparaffin pallet 90, taking on a burden.

Moreover, the evaluation technique using the strip 92 does not allow therisk of possible caries to be evaluated easily in a short time becauseit requires five minutes. Furthermore, it has another problem in thatthe used strip 92 can not be reused, leading to a increase in cost forevaluating the risk of possible caries.

In the case where an attempt is made to determine whether any carieshave developed based on the change in the strip's color after a giventime has passed, the timing of comparison with the color chart 94 is animportant factor, which imposes time constraints on the measurementprocedure. In addition, change in color of the strip 92 may vary amongthe individual strips, which disturbs the determination of the risk ofpossible caries in some cases.

This means that the conventional method of evaluating the risk ofpossible caries is prevented from convenient application because it isnot only unsanitary but also requires extensive labor and time on bothsides of the laboratory technician and the patient. For that reason,almost few patients are checked for any risk of possible caries at adental clinic and they can not well recognize their risk of possiblecaries.

In the case where a patient visits to another dentist due to, forexample the change of his/her house, the dentist should create the newmedical record of the patient and recognize the patient's mouthcondition while treating a dental disease because he/her can not knowhis/her history of disease.

The objective of the present invention, in which the solutions for theproblems mentioned above have been considered, is to provide a method ofevaluating the risk of possible caries and the device, system, andprogram of the same, which is useful for the subjects to keep theirmouth conditions best by measuring the chemical properties of salivasamples collected from the mouths of subjects to allow for easy andsanitary evaluation of the risk of possible caries in a short time andto help the subjects accurately recognize their risk of possible cariesand closely consult their dentist.

DISCLOSURE OF THE INVENTION

To attain the objective mentioned above, the method of evaluating therisk of caries in the first mode of the present invention has such acharacteristic that saliva is collected from the mouth of a subject, agiven ratio of acid is added to the saliva, and the chemical property ofthe saliva is measured to evaluate the risk of possible caries base onthe measured value.

The method of evaluating the risk of possible caries in the second modeof the present invention has such a characteristic that the saliva iscollected from the mouth of the subject, the chemical property of thesaliva is measured using a chemical property measuring device, a givenratio of acid is added to the saliva, and the chemical property ofsaliva is measured again to evaluate the risk of possible caries basedon the difference between the measured value of chemical property ofsaliva before adding acid and that after adding acid.

Thus, the method of evaluating the risk of possible caries of thepresent invention allows for the measurement of the acid buffer capacityof the subject's saliva, achieving the correct evaluation of the risk ofpossible caries. This means that the saliva can be used to evaluate therisk of possible caries because the saliva's buffer capacity regulatesthe chemical properties of saliva itself if appropriate to prevent themouth condition from being acidic, in which caries tend to easilydevelop.

Moreover, the method of evaluating the risk of possible caries using thechemical property measuring device can be repeatedly used, reducing arunning cost for one evaluation.

For that reason, if a dentist or a patient himself/herself uses themethod of the risk of possible caries of the present invention, themouth condition could be measured conveniently to obtain an objectiveindication for treatment. In addition, the dentist could give an adviceto the patient on how to prevent caries from developing and treathim/her correctly to teach the patient the method for mouth caredepending on his/her risk of possible caries. The patient would tent toadhere to the dentist's advice based on the measured data withoutanxiety, relieving a pain involved with treatment.

A more accurate quantity of acid with a given ratio to saliva could bemixed in the saliva by determining the quantity of the saliva to becollected and immersing an absorbing piece, which absorbs a given ratioof acid, in the saliva. When, in particular, a minute quantity of acidis mixed in the saliva, the given ratio of acid could be easily mixed inthe saliva samples, resulting in easy measurement by regulating thequantity of saliva to be mixed with the quantity of acid to be absorbedby the absorbing piece determined. The use of the absorbing piece makesthe mixture of a given quantity of acid into the saliva very easy,facilitating the evaluation of the risk of possible caries.

The device of evaluating the risk of possible caries in the third modeof the present invention has such a characteristic that it is composedof a container for storing the saliva collected from the mouth of thesubject, a sensor surface, which comes in contact with the saliva tomeasure the chemical property of the saliva, and a computing part forevaluating the risk of possible caries based on the measured value forthe chemical property of the stored saliva after a given ratio of acidis dropped in the saliva in the container.

The device of evaluating the risk of possible caries in the fourth modeof the present invention has such a characteristic that it is composedof a container for storing the saliva collected from the mouth of thesubject, a sensor surface, which comes in contact with the saliva tomeasure the chemical property of the saliva, and a computing part forevaluating the risk of possible caries based on the difference betweenthe measured value for the chemical property of the stored salivaimmediately after the collection and that after a given ratio of acid isdropped in.

This means that the device of evaluating the risk of possible cariesallows for more convenient evaluation of the risk of possible cariessimply using a minute quantity of saliva. In addition, since the risk ofpossible caries is output in the form of grade, the precise picture ofthe result of evaluation can be easily understood.

If the computing part has a table for storing the relationship, whichderives the grade of the risk of possible caries from the two measuredvalues got before and after adding acid to the saliva or the measuredvalue got after adding acid in the saliva, between the measured value(s)of chemical property of the saliva and the grade, more correctevaluation is achieved based on statistics derived by the measuredvalue(s).

A system of evaluating the risk of possible caries in the fifth mode ofthe present invention has such a characteristic that it is composed of ameasuring device for measuring the chemical property of the salivacollected from the mouth of the subject, a server having a databasestoring evaluation criterion data used in evaluating the risk ofpossible caries based on the measured value for the chemical property ofthe saliva to possess a risk evaluation function for evaluating the riskof possible caries for the subject using the measured value for thechemical property measured by the measuring device, a terminal having atleast a evaluation output function for outputting the result of theevaluation of the risk of the possible caries, and a network forperforming at least one of data inputs/outputs among the measuringdevice, the server, and the terminal.

For that reason, the dentist or patient can measure the chemicalproperty of sample such as saliva collected from the mouth using themeasuring device and obtain the grades of evaluation of the risk ofpossible caries. This means that the patient can accurately judgehis/her own mouth condition based on the grade of evaluation of the riskof possible caries, and actively visit the dentist for treatment, ifneeded. In other words, the risk of possible caries, which has beendifficult to determine conventionally, can be correctly recognized basedon the measured values for the chemical property of the saliva and theneed for treatment can be determined based on the grade of evaluation.

Note that the measuring device can be installed at, for example a dentalclinic, though it may be located at the subject's home and connected tothe server via a network. Similarly, the server may be installed at, forexample a dental clinic, though it may be located at the administratingfirm to administer the servers to connect a plurality of dental clinicsto them via the terminals and the network. The terminal is installed atthe dental clinic and/or the patient's home. In addition, the terminalneeds not to be a so-called terminal for connecting to the network butmay be an output device, for example a display (including a indicator ofthe measuring device), a printer, or an input device, for example akeyboard or a mouse which are directly connected to the server.

If the database contains electronic medical charts recording dentalcondition transition data composed of the measured value data for thechemical property of the saliva of the subject, it can be used intreatment because these measured values are accumulated in the databasein the form of electronic medical charts. When in particular, thepatient visits another dentist, he/she can provide the dentist withhis/her electronic medical chart to establish the better communicationwith the dentist.

If the server has a electronic medical chart browsing function forbrowsing the dental condition transition data of the subject recorded onthe medical chart by using the terminal, the subject can browse his/herown electronic medical chart to make efforts in keeping his/her mouthcondition better. On the other hand, if the dentist browses theelectronic medical chart of even new patient, he/she can recognize theirmouth condition transitions and more correctly treat him/her. Inaddition, the dentist can give an appropriate advices to every patienton how to brush teeth, how to improve eating habit, and the recommendedkind of tooth pastes to have resistivity to caries.

If the electronic medical chart contain the history of medical treatmentof the subject teeth as dental condition transition data and the serverhas an evaluation criterion create/update function for creating orchanging the evaluation criterion data by taking the statistic on themeasured value data and the history data recorded on a plurality ofelectronic medical charts, the evaluation criterion data indicting therelationship between the measured values for the chemical properties ofthe saliva samples and the grades of evaluation of the risk of possiblecaries can be refined based on the statistics of the actual data to makemore accurate evaluation of the risk of possible caries.

Note that if a researcher on the risk of possible caries participates inthe study as an administrator of the data base or the statistics of themeasured value data for the chemical properties of the saliva samplesand the dental condition transition data are provided to the researcher,the study on this subject may be promoted. For the chemical propertiesrelating to the risk of possible caries, the pH value or pH buffercapacity of the saliva samples may be considered at present, thoughother chemical properties may be measured in the future. This means thatpreferably, the kinds and values of the chemical properties to be usedas the evaluation criteria are modified or added if needed based onadvices by the researcher participating in the system for evaluating therisk of possible caries as an administrator or assistant.

If the system is composed of a terminal having an individual evaluationcriterion input function for browsing the dental condition transitiondata recorded on the electronic medical chart to create or modify theindividual evaluation criterion data refined for each subject, theevaluation criteria refined for the conditions of individual subjectscan be created to more accurately determine the risk of possible caries.

If the database contains the treatment guideline data giving theguideline for treatment in accordance with the evaluation criteria, thedental disease can be treated in accordance with the grade of evaluationof the risk of possible caries, increasing the utility value of thesystem for evaluating the risk of possible caries.

If the server has a treatment recommendation distribution function fordistributing appropriate treatment to the individual subjects inaccordance with the grade of evaluation of the risk of possible cariesvia any of electronic communication means such as e-mail, the subjectscan understand that their mouth conditions require medical treatment andundergo the treatment at an early stage without a loss of timing.

If the treatment guideline data contains the subject treatment guidelinedata for the subjects and the dentist treatment guideline for thedentists, the subjects can obtain the understandable treatment guidelinewritten in plain words, while the dentists can obtain the definitiveprofessional medical guidance, which help them improve their skill. Inthis context, the subject enjoys the safety when visiting the dentist asa patient because the dentist gives appropriate and easy explanationsfacilitating the communication between both of the dentist and subjectsides.

If the database contains a mouth condition medicine list, the subjectscan select and purchase the appropriate medicine for improving theirmouth conditions with ease. In addition, pharmaceutical companiesmanufacturing the drugs can take the sales-promotion activities simplyby registering the efficacy of their drugs in the mouth conditionmedicine list.

If the server has an inspection reservation function for accepting theevaluation of the risk of possible caries by assigning the right of useof the measuring device to the individual subjects when accessed by thesubjects via their terminals via the network, the subjects can undergothe evaluation of the risk of possible caries at a convenient time byaccessing the server via the network to reserve the measuring device,improving their convenience.

Note that the subject may measure his/her chemical properties using themeasuring device at the subject's home by sending the measuring deviceto the subject from the administrator of the system for evaluating therisk of possible caries and the chemical properties of the saliva samplemay be measured at the inspection laboratory or the administrator's siteby sending the saliva sample collected from the mouth of the subject.Moreover, the subjects may visit the inspection site arranged by thedentist or the inspection laboratory having the measuring device tomeasure the chemical properties of their saliva samples.

If the server has an evaluation distribution function for distributinggrades of evaluation of the risk of possible caries to the subjects viaany of electronic communication means such as e-mall, the subjects caneasily receive the grades of evaluation and treat appropriatelyaccording to them.

The server contains a dentist list, a dentist, who participates in thesystem for evaluating the risk of possible caries, may be introduced tothe patient. For that reason, the subjects can easily identify thedentist, who correctly treats based on the correct determination usingthe system for evaluating the risk of possible caries.

If the server has a treatment reservation function for reserving thetreatment by the dentist, who is included in the dentist list, byaccessing from the subject's terminal via the network, the subject canreserve the treatment without the need for visiting or calling thedentist in the dentist list, improving his/her convenience. The dentistscan accept their patients simply by registering in the system forevaluating the risk of possible caries of the present invention.

If the server has a regular inspection recommendation function fordistributing the recommendation of regular inspection to the subjectsdepending on their grades of evaluation of the risk of possible cariesvia any of electronic communication means such as e-mail, it can berecommended that preferably, the subjects undergo the regular inspectionat an interval adjusted for each of the subjects, which enables thesubjects to eliminate the need for unwanted inspections and rememberonly the required ones.

The program of evaluating the risk of possible caries in the six mode ofthe present invention has such a characteristic that it involves a stepfor obtaining the measured value for the chemical property of the salivacollected form the mouth of the subject, a step for referring to theevaluation criterion data in evaluating the risk of possible cariesbased on the measured value for the chemical property contained in thedatabase, and a step for outputting the obtained measured value for thechemical property in the form of the grade of evaluation of the risk ofpossible caries based on the evaluation criterion data, and that thesesteps are performed by a computer.

If using this program, the server obtains the measured values via thecommunication network or when an operator enters the sent measured datain the computer to obtain the measured values, refers to the evaluationcriterion data contained in the database, makes the evaluation of therisk of possible caries, and outputs the grade of evaluation to theprinter, display unit or communication network, the mouth conditions canbe easily and accurately recognized. In this case, a function forstoring the dental condition transition data of the subject containingthe measured values for the chemical properties in the database as anelectronic medical chart may be added to the program to be executed bythe server.

The method of evaluating the risk of possible caries in the seventh modeof the present invention has such as characteristic that it measures thechemical property of the saliva collected from the mouth of the subjectand outputs the measured value for chemical property in the form of thegrade of evaluation of the risk of possible caries of the subject byreferring to the database recording the evaluation criterion data forevaluating the risk of possible caries in accordance with the measuredvalue, creates an electronic medical chart recording the dentalcondition transition data containing the measured value for the chemicalproperty of the subject's saliva, and performs at least one of input ofthe measured value for the chemical property, reference to the database,and output of the grade of evaluation of the risk of possible cariesthrough data communications via a network.

This means that by applying any information communications technology,convenience can be improved and the subject can accurately recognizetheir own mouth condition based on the measured values for the chemicalproperties.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a view showing one example of a device of evaluating the riskof possible caries of the present invention.

FIG. 2 is a view explaining one example of a method of evaluating therisk of possible caries of the present invention.

FIG. 3 is a view showing the result of the measurement of the chemicalproperties of a plurality of saliva samples.

FIG. 4 is a view explaining another example of the method of evaluatingthe risk of possible caries.

FIG. 5 is a view showing the whole configuration of a system ofevaluating the risk of possible caries of the present invention.

FIG. 6 is a view showing one example of a measuring device used in thesystem of evaluating the risk of possible caries.

FIG. 7 is a view showing one example of a screen, which can be browsedby subjects using a server of the system of evaluating the risk ofpossible caries.

FIG. 8 is a view showing another example of the screen.

FIG. 9 is a view showing further another example of the screen.

FIG. 10 is a view showing a screen, which can be browsed by dentistsusing the server of the system of evaluating the risk of possiblecaries.

FIG. 11 is a view explaining one example of a conventional method ofevaluating the risk of possible caries.

BEST MODE FOR CARRYING OUT THE INVENTION

FIG. 1 is a view showing the whole configuration of one example of adevice 1 of evaluating the risk of possible caries of the presentinvention. In FIG. 1, 2 indicates a main body, 3 indicates a sensorpart, which can be detachably attached to the main body 2, and 4indicates a rid, which can be detachably covered to the sensor part 3.

The main body 2 is composed of a computing part 5 for computing thegrades of evaluation of the risk of possible caries using a pH value asone example of the chemical properties of saliva samples to be measuredin the sensor part 3, a display part 6 for displaying at least thegrades of evaluation of the risk of possible caries computed in thecomputing part 5, and a operating buttons 7 for operating the device 1of evaluating the risk of possible caries. The operating buttons 7include, for example a power button 7 a and a measurement button 7 b.

The sensor 3 is composed of a sensor surface 8, which has been made byarranging, for example an ISFET measuring electrodes and comparisonelectrode on the same plane and a container 10 for storing the salivasamples collected from the mouths of the subjects, which are constructedso that the sensor surface 8 forms its bottom. Note that the sensorsurface 8 of the example is made from the ISFET measuring electrodes forpH measurement and the comparison electrodes because it shows the casewhere the grade of evaluation of the risk of possible caries isdetermined based on the pH measured values, though alternatively,instead of pH, ORP measured values or any of other chemical propertiessuch as other ion (for example, calcium ion) concentration and proteinquantity may be used as a determination criterion.

In addition, such a method may be considered that a plurality ofchemical properties are measured to comprehensively determine theindividual chemical properties for evaluating the risk of possiblecaries. It does without saying that electrodes composing the sensorsurface 8 should be changed in the case where other solution propertyparameters including ORP and calcium ion are measured.

The use of ISFET in the sensor surface 8 enables the required quantityof the saliva sample 15 to be reduced, though the present invention doesnot limit the kind of ion electrodes composing the sensor 8 to ISFBT andminiaturized regular glass electrodes or flat glass electrodes may beused.

The rid 4 is rotatably attached to the main body 2 by a hinge 9 and iscomposed of a rid main body 11 forming a sealing part 4 a, which iswater-tightly engaged with the edge of the container 10 with the rid 4closed and an opening 4 b in the upper part of the container 10 and amovable element 12 for closely switching the opening 4 b when slidablyengaged with the rid main body 11. To prevent the saliva samples 15 fromleaking from the container 10, it is an important factor to closely sealthe container, though the present invention does not limit theconfigurations of the rid 4 and other members.

FIG. 2 is a view explaining the method of evaluating the risk ofpossible caries using the device 1 of evaluating the risk of possiblecaries. Now, one example of the method of evaluating the risk ofpossible properties is described below in reference to FIGS. 2 and 3.Namely, the use of the device 1 of evaluating the risk of possiblecaries enables the risk of possible caries may be evaluated easily. Onthe other hand, in the method of evaluating the risk of possible cariesof the present invention does not limit to the use of the device 1 ofevaluating the risk of possible caries.

First, as shown in FIG. 2A, for example a sterilized syringe 13 is usedto collect the saliva sample from the subject 14. At that time, thequantity of the saliva sample to be collected is the quantity requiredfor measurement, and it depends on the capacity of the sensor 3. If theISFET sensor surface 8 is formed as shown in this example, it issatisfactory to collect 0.5 mL or more saliva and is checked at thedivisions (not indicated) marked on the syringe 13. Note that thesubject 14 may bite a paraffin palette 90 in the conventional manner toinduce the secretion of saliva for collection.

As shown in FIG. 2B, the collected saliva 15 is checked at the divisionson the syringe 13 and 0.5 mL of saliva is dropped on the sensor surface8, for collecting it in the container 10. At that time, the salivasample 15 may be stored in the container 10 with the rid main body 11open or collected it through the opening 4 b by opening the removableelement 12 with the rid main body 11 closed. Note that the presentinvention does not limit the quantity of the saliva sample 15 to be usedin evaluating the risk of possible caries and more minute quantity ofsaliva sample 15 may be used for measurement depending on theperformance of the senor surface 8.

Second, the operating button 7 b is pressed to measure the pH value forthe saliva sample 15. Note that the power on the device 1 of evaluatingthe risk of possible caries may be turned on prior to measurement orimmediately before the pressing the operating button 7 b. Alternatively,the initial pH measurement may be autonomously started when the salivasample 15 begins to be dropped on the sensor surface 8.

As soon as pH measurement is finished, the pH value is stored and amessage for requesting the drop of acid is output by issuing an acousticor visual alarm to the operator.

FIG. 2C is a view showing a step for mixing a given ratio of acid 16 inthe saliva sample 15. The acid 16 to be used here is 0.1 mol/L ofhydrochloric acid solution and 10 μL is measured using a desiredchemical feeder 17 for infusion. (Namely, 0.000002 g equivalent weightto the saliva sample 1 mL).

FIG. 2D is a view showing a step for mixing the infused acid 16 in thesaliva sample 15. At that time, the container 10 can be hermeticallyclosed by fully closing the rid main body 4 to prevent the saliva sample15 from leaking hen the device 1 of evaluating the risk of possiblecaries is well shaken in order to mix the saliva sample 15 and the acid16 sufficiently.

It is desired that the time of the saliva sample 15 being left is setusing the program to be executed in the computing part 5. This meansthat the computing part 5 waits for, for example 30 seconds sincepressing the measurement button 7 b and then outputs the message forrequesting the second pH measurement by issuing the acoustic or visualalarm, allowing for stable measurement with no complex labor.

Then, as soon as the pH values has been measured immediately after the10 μL of hydrochloric acid solution is mixed, the device 1 of evaluatingthe risk of possible caries outputs the message for requesting droppingof 10 μL of hydrochloric acid again to the operator to repeat the stepsin FIGS. 2C and 2D. Thus, by dropping the hydrochloride acid three timesand measuring any variation in pH value, any change in pH value ismeasured when 30 μL of hydrochloride acid solution (a given ratio ofacid 16 by 0.000006 g equivalent weight to 1 mL of saliva) in total ismixed in 0.5 mL of saliva sample 15.

As shown in this example, by adding a 0.000002 g (equivalent weight)aliquot of acid 16 to 1 mL of saliva three times and measuring anyvariation in pH value each time, the pH buffer capacity of the salivasample 15 can be more accurately determined. However, it goes withoutsaying that a given ratio of acid 16 may be dropped at the same time forobtaining the final result. In this case, the time required formeasurement is shorten.

Finally, the saliva sample 15, which has been used for pH measurementafter the mixture of acid 16, is discarded and the inside of thecontainer 10 is washed to prepare for the measurement of the next salivasample. Namely, this method requires no disposable inspection elements,—for example a strip 92 in the conventional method, reducing the cost ofmeasurement.

FIG. 3 is a view showing the result of the measurement of any variationin pH when 0.1 mol/L hydrochloride acid solution is dropped by 10 μL formixing in the 0.5 mL of saliva sample 15 collected from each of 15subjects. As shown in FIG. 3, when 30 μL of hydrochloride acid solutionwas dropped, a large variation was observed in pH value of the salivasample 15 for each subject, which may be measured to use a marker of thebuffer capacity of each of the saliva samples 15. Namely, based on thevariation in pH value of the saliva sample 15, the pH buffer capacity ofthe saliva sample 15 for each subject can be accurately evaluate.

The evaluation may be performed by referencing to a table recorded inthe computing part 5 or a recording medium in other part. The tablegiven in this example describes the staged grades of evaluation of therisk of possible caries for the pH values of the saliva samples 15measured after acid was dropped and specifically, it can be determinedthat the saliva sample 15 with 5.7 or higher pH, when measured after 30μL of hydrochloride acid solution being dropped, has a statisticallylower risk (LEVEL0) of possible caries. It also can be determined thatthe saliva sample 15 with 5.4 or higher and 5.7 or lower pH has a mediumrisk (LEVEL1) of possible caries and the saliva sample 15 with pH lowerthan 5.3 has a higher risk (LEVEL2) of possible caries. Note that theseranges described here do not limit not only the scope of the presentinvention but also the risk of possible caries to the three-levelrepresentation.

In any cases, since the pH value measured after 30 μL of hydrochlorideacid solution being dropped indicates the buffer capacity of the salivasample 15 to acid, the risk of possible caries may be easily determinedbased only on the pH value measured after 30 μL of hydrochloride acidsolution being dropped. However, the present invention does not limitthe evaluation of the risk of possible caries to the use of the pH valuemeasured after 30 μL of hydrochloride acid solution being dropped.

This means that the table does not limit the computation of the stagedgrades of evaluation of the risk of possible caries to the use of pHvalue measured after acid was dropped. Namely, the risk of possiblecaries may be evaluated taking the pH value measured before acid wasdropped into account together with that measured after acid beingdropped. In other words, based on the pH value measured before acid wasdropped, the risk of possible caries may be evaluated in the usual stateand the properties of saliva secreted by the subject may be evaluatedusing the paraffin pellet 90 and the like. Based on any differencebetween the pH values measured before and after acid was dropped, therisk of possible caries can be evaluated more accurately. In addition,various modes of tables may be considered, for example to enabledetailed evaluation based on the time-course change in pH after acid wasadded.

Furthermore, the grades of evaluation of the risk of possible caries arenot limited to one-digit representation. Namely, the incident factor ofcaries in the usual state may be derived based on the initial pH valueto derive the incident factor of the resistivity to caries based on thebuffer capacity to acid 16. In any cases, by representing the risk ofpossible caries in the form of the grade of evaluation of the risk ofpossible caries rather than in the form of pH measured values, theoperator can determine easily the risk of possible caries.

Besides, the present invention does not the quantity of acid 16 to bedropped on the saliva sample 15 to its optimal condition (0.000006 gequivalent weight to 1 mL of saliva). It is understood from FIG. 3 thatsince even though the quantity of acid 16 to be mixed in the salivasample 15 is reduced to lower than the value mentioned above, forexample 20 μL of 0.1 mol/L hydrochloride acid solution is dropped on 0.5mL of saliva sample 15 (0.000004 g equivalent weight to 1 mL of saliva),the pH value of the saliva sample 15 with higher risk of possible cariesdecreases due to the influence of mixed acid 16, this ratio of acid 16is uniformly dropped on all the saliva samples 15 to evaluate the riskof possible caries.

Even if the quantity of acid 16 to be mixed in the saliva sample 15 isincreased compared with that mentioned about (0.000006 g equivalentweight to 1 mL of saliva), the risk of possible caries may be evaluatedin the range where the saliva sample with lower risk of possible cariesexhibits the pH buffer capacity to mixed acid 16 by dropping the samegiven ratio of acid 16 on all the saliva samples 15.

Again, although the example describes the use of the hydrochloridesolution as an example of acid 16, the present invention does not limitthe kind of acid 16 only to hydrochloride acid. In the case ofhydrochloride acid, 0.1 mol of hydrochloride acid is mixed in the 1 L ofsolvent, though it goes without saying that the quantity of other acid16 depends on its property to chemical reaction.

In the example mentioned above, the method of evaluating the risk ofpossible caries using the device 1 of evaluating the risk of possiblecaries having the function for evaluating the risk of possible carieshas been described, though in the method of evaluating the risk ofpossible cries, any of standard devices of measuring the chemicalproperties may be used such as a commonly used pH measuring device. Inthis case, a correspondence between pH measured values is provided asshown in FIG. 3 for the operator to refer to it to evaluate the risk ofpossible caries based on the two pH measured values using the commonlyused pH measuring device converted into the grades of evaluation.

By forming a storing part for acid 16 and a dispensing part for acid 16on the device of evaluating the risk of possible caries as shown in theexample mentioned above, a given quantity of acid 16 may beautomatically dispensed on the saliva samples 15. In this case, theoperator needs not use extra devices such as a drug solution injector 13for acid addition. Furthermore, by attaching a sensor for measuring thequantity of the saliva sample 15, the quantity of acid 16 may beautomatically regulated to that of the saliva sample 15.

FIG. 4 is a view showing an example of another technique for mixing acid16 in the method of evaluating of possible caries. FIGS. 4A and 4B arethe same as FIGS. 2A and 2B, each showing the step for collecting thesaliva samples 15 and the step for dropping the collected saliva samples15 on the device 1 of evaluating the risk of possible caries.

FIG. 4C shows a step for mixing acid 16 in the saliva samples 15 in thecontainer 10 using the absorbing pieces soaked with acid 16. 18indicates a test strip as an example of the absorbing piece and the teststrip 18 has been soaked with 0.000003 g equivalent weight of acid 16 sothat a given ratio to 0.5 mL of saliva may be established. For thatreason, simply by soaking the test strip 18 in the saliva samples 15, anaccurate given ratio of acid 16 may be mixed in the saliva samples 15.

Then, the pH values of the saliva samples 15 with acid 16 mixed ismeasured to evaluate the risk of possible caries. As shown in thisexample, the use of the test strip 18 makes the mixture of the givenratio of acid 16 in the saliva samples 15 easier, further saving theoperator's labor.

Note that in the examples mentioned above, the techniques for droppingthe aqueous acid solution have been described, though the presentinvention does not limit acid only to this type of phase. Namely, suchtechniques may be used that a given quantity of acid in the solid phaseat room temperatures such as citric acid is added after transformed intopowder or pellets.

FIG. 5 is a view showing one example of a system 20 of evaluating therisk of possible caries of the present invention. The descriptions ofthe portions in FIG. 5 having the same symbols as those in FIG. 4 areomitted because they are the same or equivalent portions. 1A indicates ahandy (stick) type of measuring device for the subject 14 to measure thechemical properties of the saliva sample collected from his/her ownmouth.

In FIG. 5, 21 indicates a server for evaluating the risk of possiblecaries for the subject 14 from measured chemical properties, 22indicates, for example a database concluded in memory of the server 21,23 indicates a terminal having a function for outputting a evaluation ofthe risk of possible caries, and 24 indicates the internet as oneexample of networks connecting among the measuring device 1A, 1B, 1C . .. the server 21, and the terminal 23.

The terminal 23 in this example having, for example any of informationprocessing devices such as a PC and server, is composed of the terminal23A installed at the home 25 of the subject 14, the terminal 23Binstalled at a dental clinic 26 for the dentist 27 to operate, theterminal 23C installed at the inspection firm 26′ for the laboratorytechnician 10′ to operate for measuring chemical properties of thesamples collected from the mouths of the subjects 14, and the terminal23X installed in the laboratory for a researcher 28, who makes a studyon dental sanitation, for scholars 29 to operate and each terminal 23A,23B, 23C and 23X may be installed in various places connected via theinternet 24.

On the other hand, the server 21 in this example is for executing aprogram P of evaluating the risk of possible caries and is aninformation processing device installed at a database administrationfirm 30 for making inspections on the risk of possible caries andadministrating the database 22, and it is operated by an administrator31 of the database 22. However, the servers 21 may be installed at eachof the dental clinic 26 or the inspection firm 26′ and administrated bythe dentist 27 or the laboratory technician 10′. In this case, theexisting information processing devices installed in the dental clinic26 and the inspection firm 26′ (in this example, terminals 23B and 23C),if any, may be used as the servers 21.

It goes without saying that the database 22 is not necessarily recordedin memory of the server 21 and another server may be added foradministrating the database 22. On the other hand, as shown in thisexample, if the administration firm 30 administers the database 22,information can be managed beyond the extent of the dental clinic 26 anda wide variety of information useful in evaluating the risk of possiblecaries can be collected as described later.

The measuring devices 1A, 1B and 1C measure the pH values and pH buffercapacities of the saliva samples collected from the mouths of thesubjects 14 as chemical properties. Various types of measuring devices1A, 1B and 1C may be used, and a stick type of measuring device 1A,which has been designed so that the subject 14 can connect them tohis/her terminal 23A via a given standard of interface, for example USBat his/her home, can be given an example.

For the types of the measuring devices 1A, 1B and 1C any stationarymeasuring device 1B can be used, which has been designed so that it maybe connected to the terminals 23B and 23C via the given standard ofinterface, for example USB, installed at the dental clinic 26. As themeasuring devices 1B and 1C shown in FIG. 5, a display 1 a having thefunction for displaying the measured values for the chemical propertiesor outputting the grades of evaluation of the risk of possible cariescan be used to serve also as the terminal 23.

In addition, the measuring device 1B may have the same function as thatof the terminal 23 by connecting it directly to the internet 24.Furthermore, the measuring device 1C administered by the inspection firm26′ may be used instead.

The database 22 is composed of electronic medical chart 32 containingthe month condition transition data 32A, individual data 32B on thesubject 14, and the individual evaluation criterion data 32C describedlater, the evaluation criterion data 33 indicating at least therelationship between the measured values for the chemical properties andthe grades of evaluation of the risk of possible caries, the registereddentist data 34 indicating the information on the registered dentistscooperating in the system of evaluating the risk of possible caries ofthe present invention, and the mouth condition medicine data 35indicating the information on the recommended mouth condition remedies.

The mouth condition transition data 32A is composed of the measuredvalue data 32 a consisting of, for example the history of the measuredvalues for the chemical properties of the saliva samples collected formthe mouths of the subjects 14 and the history of dental treatment data32 b of the subjects 14, which are medical treatment data specific tothe subject 14, where the dentist 27 adds the descriptions. Theindividual data 32B is composed of, for example the information on theaddresses, names, ages, genders and contacts (including e-mailaddresses) of the subjects 14. In addition, the individual evaluationcriterion data 32C is a group of individual evaluation criteria refinedfor each of the conditions of the subjects 14.

For the evaluation criterion data 33, not only the data indicating therelationship between the measured values for the chemical properties andthe grades of evaluation of the risk of possible caries, but also, forexample the statements “urgent treatment is needed”, “the diagnosis by adentist is recommended”, “the regular inspection is recommended”, and“no risk of possible caries is observed at present” and the guidelinefor preventing caries from developing, for example the number of toothbrushing a day may be included. It is desirable that the generaltreatment guideline 33 a, which is easy for the subjects 14 to recognizeand the professional treatment guideline 33 b, which provides thedentist with a plenty of information described later are individuallyincluded in treatment guideline.

Moreover, similarly, it is desired that the treatment guideline data inthe form of statements is contained in the evaluation criteria recordedas the individual evaluation criterion data 32C, and the generaltreatment guideline, which is easy for the subjects 14 to understand,and the professional treatment guideline, which provides the dentistswith a plenty of information are individually included.

Note that in any cases, in this example, the treatment guideline datahas been included for outputting the treatment guideline (statements)corresponding to the grades of evaluation as part of the evaluationcriterion data, though they may be separated into two parts and storedin the database.

FIG. 6 is a view explaining one example of stick type of measuringdevices 1A. Note that since the measuring device 1A in this examplecomposes part of the device 1 of evaluating the risk of possible cariesshown in FIG. 1, the duplicated explanation of the same or equivalentportions are avoided using the same symbols as those in FIG. 1.

In FIG. 6, 1 b indicates a cable connecting a main body 2 of themeasuring device 1A to the terminal 23A (refer to FIG. 5) via forexample USB. Since the measuring device 1A in this example ispower-supplied while connecting to the terminal 23 A, only a measurementbutton is satisfactory for the operating button 7.

The measured values S₀ for the chemical properties measured by thesensor surface 8 of the measuring device 1A are designed so that theymay be sent to the terminal 23A via the signal cable 1 b and sent to theserver 21 via the terminal 23A.

In the case where the subject 14 shown in FIG. 5 accesses the server 21via their own terminals 23A to submit the application for using thesystem of evaluating the risk of possible caries, they can create themedical charts 32 of the subject 14 in the database 22 and receive themeasuring device 1 from the inspection firm 26′ (or from the dentist 10or the database administration firm 30). In this case, to create thecorrect electronic medical chart 32, the history of dental treatment ofthe subject 14 and the like should be browsed on the web or the writtenmedical records sent. At the same time, the ID or password of thesubject 14 is determined, which are needed in using the system 20 ofevaluating the risk of possible caries of the present invention.

Namely, the server 21 has an inspection reservation function foraccepting the grades of evaluation of possible caries and assigning theright of use of the evaluation system server 21 of the present inventionto each of the subjects 14 when accepting the application for using thesystem and sending the usable measuring device 1A to the subject 14.Note that the application for using the evaluation system is not limitedto the use of the internet 24 and may be made by sending a given form ofapplication, in which required data is filled by the subject 14, to theinspection firm 26′.

The subject 14 connects the measuring device 1A, once received athid/her home 25, to the terminal 23A and measures the chemicalproperties of the saliva samples collected from his/her own mouth. Sincethe method of measuring the chemical properties using the measuringdevice 1 has been described in reference to FIGS. 2 and 4, the detailedexplanations of it is omitted here.

The subject 14 presses the operating button 7 to measure the pH value ofhis/her saliva sample 36. At that time, as shown in this example, sincepower is supplied to the measuring device 1A from the side of terminal23A, the operation of the power source can be eliminated or streamlined,though it goes without saying that another power source may be added.

Once the pH value has been measured, the computing part 5 stores themeasured pH value and then the message requesting the subject 14 to dropacid 16 supplied with the measuring device 1A from the inspection firm26′ on the saliva sample 15 with a acoustic or visual alarm. Then, thesubject 14 drops acid 16 on the saliva sample 15, well shakes themeasuring device 1 for mixture, and leaves it for a given time (approx.thirty sec. to one min.) to make the second measurement of pH value.

It is desirable that the time for which the sample is left is set usingthe program to be executed in the computing part 5. Thus, by droppinghydrochloride acid solution on the saliva sample three times andmeasuring any variation in pH value each time, a change in pH value ismeasured immediately after 30 μL of hydrochloride acid solution (a givenratio of acid 16 by 0.000006 g equivalent weight to 1 mL of saliva) hasbeen mixed in 0.5 mL of saliva sample 15 to measure pH value and pHbuffer capacity of the saliva sample 15.

The measured values S₀ such as the measured pH value and pH buffercapacity are accumulated in the database 22 in the server 21 via theterminal 23A and the Internet 24, and the server 21 outputs the measuredvalues S₀ for chemical properties to the terminal 23A after convertingthem into the grades S₁ of evaluation of the risk of possible caries andthe treatment guideline 33 a in reference to the evaluation criteriondata 33 using the program P of evaluating the risk of possible caries.

The evaluation criterion data 33 indicates a relationship obtained basedon the actual measured values as detailed above with reference to FIG.3, which has been represented in the form of a table.

Note that an individual difference may be observed in the development ofthe pH buffer capacity after acid 16 has been dropped. Thus, using thesystem 20 of evaluating the risk of possible caries of the presentinvention, the condition transition data 32A of a plurality of subjects14 is used to compare between the measured values for chemicalproperties of the collected saliva samples and the history of dentaltreatment of each of the subjects 14, which allows for creating of orupdating to more actual evaluation criterion data 33. On the other hand,based on the history of treatment for each of the subjects, theindividual evaluation criterion data 32C may be created taking theirunique characteristics into account.

The individual evaluation criterion data 32C may be created or updatedby the dentist 27, who examined the subject 14, entering data from theterminal 23B, to store it in the database 22. Then the accurateindividual evaluation criterion data 32C is created by a high ability ofthe dentist 27. At the same time, additional data such as the treatmentguideline represented by means of statements may be also included by thedentist 27.

Note that as shown in FIG. 5, the grads S₁ of evaluation of the risk ofpossible caries may be distributed to the subject 14 in the form ofe-mall. Namely, the server 21 has the function for distributing thegrades of evaluation of the risk of possible caries to the subject 14using e-mall and the like.

In addition, the server 21 preferably has the function for distributingthe recommended treatment to send the treatment guideline 33 acontaining an appropriate advice and the recommended treatment to thesubject 14 with a lower grade S₁ of evaluation of possible caries bye-mall and the like.

Note that the measuring device 1 of the present invention is not limitedto those shown in the examples mentioned above and those may be usedwhich has a sensor for measuring the chemical properties and actuallyobtains the measured values. For that reason, the measuring device 1A ofwhich design is simplified and disposable, may be used. In this case,the measuring device 1A enjoys an advantage that it can make the bestmeasurements at a high accuracy without need for maintenance. On thecontrary, like the measuring devices 1B and 1C shown in FIG. 5, astationary type of measuring device, which is robust, may save the costof single measurements.

The subject 14 can access the server 21 using the terminal 23A and enterhis/her ID or password to browse his/her electronic medical chart 32.This means that the sever 21 has the function for browsing theelectronic medical charts using the terminal 23A to browse the mouthcondition transition data of the subject 14 consisting of the measuredvalues 32 a for the chemical properties and the history of treatment 32b and the like.

It is desirable that the subject 14 having the ID and password canaccess the server 21 to accumulate the questions about how to keep themouth condition better, which are to be consulted with the dentist, inthe database 22 and the administrator 31 can distribute the appropriateanswers to the questions accumulated in the database 22 via e-mall.Namely, it is preferable that the server 21 has the mouth conditionconsultation function for not only accumulating the questions about howto keep the mouth condition better but also distributing the advices bythe professionals to the subject via e-mail and the like.

FIG. 7 is a view showing the example of the screen 40 displaying theelectronic medical chart 32, which can be browses by the subject 14 whenaccessing the server 21. In FIG. 7, 41 indicates the individualinformation 32B such as the name and contact such as an e-mall addressof the subject 14, 42 indicates the history of treatment such as theresults of inspections, which have been made by the subject 14 so farand the mouth condition transition data 32A such as the measured valuesfor the chemical properties obtained at the points when the inspectionswere made, and 43 indicates the grades of evaluation of the risk ofpossible caries for the subject 14.

The history of treatment 42 is used for disclosing briefly both of themeasured value data 32 a and the history of treatment data 32 b to thesubject 14 including the dates of inspections or treatments and theirdescriptions of them. The subject checks the screen, on which thehistory of treatment 42 is displayed, to recognize the transition inhis/her mouth condition.

The grades of risk evaluation 43 includes the grades of evaluation ofthe risk of possible caries 43 a and the treatment guideline 43 b, whichare derived based on the measured values S₀ for the chemical propertiesobtained from the last inspection made by the server 21 taking theindividual information on the subject 14 into account. In addition,since the treatment is recommended on the treatment guidance 43 b inthis example, a link button 43 c to the dentist list display screen andthe link button 43 d to the mouth condition medicine list display screenappear on the screen. It is well understood that the subject 14 canclearly understand his/her own mouth condition and required treatmentsimply by browsing the risk evaluation 43.

The grades 43 a of evaluation of the risk of possible caries may be notonly based on the evaluation criterion data 33 but also based on theindividual evaluation criterion data 32C described later if it has beeninput.

FIG. 8 is the screen 50 displaying the registered dentist list appearingwhen the subject 14 presses the link button 43 c. In FIG. 8, 51indicates the screen displaying the registered dental clinic name listrecorded in the database 22 as the registered dentist data 34, 52indicates the address list of dental clinics, and 53 indicates thereserved date reference button for each dental clinic. Note that thesescreens displaying these lists 51 and 52 are preferably arrangedstarting from the closest one to the address of the subject 14.

This means that the subject 14 can select the dental clinic close tohis/her address, which treats correctly him/her using the system 20 ofevaluating the risk of possible caries simply by browsing the screendisplaying the registered dentist list 50. On the other hand, the dentalclinics may accept the patients by registering in the database 22.

By creating the reservation date reference button 53 on the screen 50displaying the registered dentist list, the subject 14 can check thereservation status of the selected dental clinic. In this case, theserver 21 receives the reservation date information 26 a (refer to FIG.5) recorded in the terminal 23B installed at the dental clinic 26 viathe internet 24, discloses it to the subject 14 and transfers thereservation contents on the subject 14 to the terminals 23B, 23C . . .isntalled at the dental clinics 26 to mediate between the patients andthe dentists in the dentist list. Namely, the server 21 has thetreatment reservation function which can accepts the application fortreatment by a dentist by mediating between the patients and thedentists in the registered dentist data 17 when the subject 14 accessesfrom the terminal 23A via the network.

Thus, the convenience of the subject 14 increases because the subject 14may reserve the desired date for treatment without the needs for visitto or calling up the dental clinic.

For that reason, on the dentist 27 side, the subject 14, who has made aquery, may be easily identified using the system of evaluating the riskof possible caries and the subject 14 can undergo the appropriatetreatment without additional labor because the dentist may refer to thehistory of treatment recorded in the electronic medical chart.

Note that in the case where the dental clinic 26 has established its ownhome page to allow the patients to reserve the treatment via theInternet 24, using a link to the home page of the dental clinic 26, themediation can be performed between the patents and the dental clinicsusing the treatment reservation function.

FIG. 9 is a view showing the screen 60 displaying the mouth conditionmedicine list appearing when the subject 14 presses the link button 43 dfrom the screen 40 displaying the electronic medical chart 32 shown inFIG. 7. In FIG. 9, 61 indicates the list of the names of the mouthcondition remedies recorded in the database 22 as mouth conditionmedicine data 35, 62 indicates the list of efficacies of the mouthcondition remedies, and 63 is a button for displaying the detailedinformation on the mouth condition remedies or for purchasing them. Notethat the server 21 preferably displays the contents of the mouthcondition medicine list starting from the one with the highest efficacy.

This means that the subject 14 can very easily identify and purchase thenecessary medicine for improving his/her mouth condition. On the otherhand, the pharmaceutical company can accept queries about their drugs byregistering the efficacies of the developed drugs in the database 22 asthe mouth condition medicine data 35. Note that those referred to as“drugs” in the present invention include various types of mouth careproducts used in treating and preventing caries. Moreover, as indicatedby a symbol 64 in FIG. 9, the comments by the administrator 31 of thedatabase 22 may be annotated to the data.

FIG. 10 is a view showing the screen 70 displaying the electronicmedical chart for the subject 14 obtained when the dentist 27 accessesthe sever 21 via the terminal 23B. In FIG. 10, 71 indicates the minimumindividual data 32B of the subject 14 including his/her name, age, andoccupation which are necessary for treatment, 72 indicates the historyof inspections which the subject 14 have undergone so far, 73 indicatesthe history of treatment which the subject 14 have received so far, and74 indicates the treatment guideline for the subject 14.

The screen 70 displaying the electronic medical chart in this example isdifferent from the screen 40 displaying the electronic medical chartshown in FIG. 7 in that the former has not only a button 72 a fordisplaying the detailed information on the inspections and a button 73 afor displaying the detailed information on the treatments but alsocontents of the treatment guideline 74 is satisfactory for the dentist27. For that reason, the dentist 27 can obtain accurate information onthe subject 14, even though he visits him for the first time, to treatthe subject 14 correctly.

Furthermore, the subject 14, who visits the dental clinic 26 as apatient, can undergo the appropriate treatment and establish the smoothcommunication with the dentist 27 without the need for providing thedentist 27 with the detailed information on himself/herself. Inaddition, in the case where the subject 14 visits another dentist due tothe change his/her residence to another one, the subject 14 can undergothe treatment by the new dentist with safety because he/she can have asufficient of knowledge of the subject 14.

The dentist 27 can enter the detailed information (including thetreatment date and the therapeutic method used) on the result oftreatment using the terminal 23B after the treatment to update his/herinformation in the electronic medical chart. Moreover, the dentist 27can modify the evaluation criterion for the subject 14 if necessary andregister it as the individual evaluation criterion data 32C in theelectronic medical chart. In addition, the treatment guideline data canbe as additional data to this individual evaluation criterion data 32Cfor giving an appropriate advice to the subject 14.

Note that as known from this example, it is preferable that for thedentist 27 to obtain the detailed information on the inspections,treatments, and treatment guideline, both of the information to bedisclosed to the subject 14 and the information to be disclosed to thedentist 27 are accumulated. For the treatment guideline data 33, inparticular, both of the subject treatment guideline data, which iswritten in the language easily understood by the subject 14, and thedentist treatment guideline, which gives the dentists with definitiveinformation, are recorded.

Besides, it is also preferable that the treatment guideline 33 iscreated and updated so that it can be made more and more practical thecontents of the database 22 improves. This means that if the detailedinformation on the evaluation criteria is gotten by taking statistic ofthe measured value data 32 a for the chemical properties and the historyof dental treatment data 32 b, then multi-levels of risk evaluation canbe performed, the treatment guideline data corresponding to the resultsof the multi-levels of risk evaluation can be added.

In addition, by taking statistic of the individual evaluation criteriondata 32C to which the dentist 27 added information and the conditiontransition data 32A, the database administrator 31 and the researcher 29can create or update the evaluation criterion data 33, which is mademore practical.

Moreover, if it is determined to be desirable to measure the chemicalproperties other than pH in the future, the new chemical properties canbe added by replacing the sensor part 21 shown in FIG. 6.

Furthermore, the interval, at which the subject 14 undergoes thetreatment, can be adjusted if necessary. Namely, if the server 21 hasthe regular inspection recommendation function for distributing theregular inspection recommendation to the subject 14 via e-mall and thelike, the subject 14 can undergo the appropriate treatment before thecaries become severe simply by receiving the inspection at an adequateinterval.

Note that the e-mall messages are preferably distributed on the day asclose as the day on which the inspection will be made. Thus, the subject14 can undergo the regular inspection on a schedule.

INDUSTRIAL APPLICABILITY

As mentioned above, according to the method of evaluating the risk ofpossible caries of the present invention and the device of the same, therisk of possible caries can be easily and promptly evaluated, saving theoperator's (or the user's) labor and time. In addition, since thechemical properties of saliva can be measured using electricaltechniques, enabling repetitive measurement, which saves the runningcost. In addition, the method of evaluating the risk of possible cariesof the present invention is sanitary because the laboratory techniciansneed not contact directly the saliva samples.

Furthermore, according to the system of evaluating the risk of possiblecaries of the present invention, and the method, and the program of thesame, the subject can conveniently undergo the evaluation of the risk ofpossible caries to obtain the appropriate treatment guideline. Inaddition, smooth communication may be established between the newsubject and the dentist, being useful for both of the patients anddentists.

1. A method of evaluating the risk of caries having such acharacteristic that saliva is collected from the mouth of subject, agiven ratio of acid is added to the saliva, and the chemical property ofthe saliva is measured to evaluate the risk of possible caries based onthe measured value.
 2. A method of evaluating the risk of caries havingsuch a characteristic that the saliva is collected from the mouth of thesubject, the chemical property of the saliva is measured using achemical property measuring device, a given ratio of acid is added tothe saliva, and the chemical property of saliva is measured again toevaluate the risk of possible caries based on the difference between themeasured value of chemical property of saliva before adding acid andthat after adding acid.
 3. The method of evaluating the risk of cariesaccording to claim 1, further comprising that acid is mixed in thesaliva by determining the quantity of the saliva to be collected andimmersing an absorbing piece, which absorbs a given ratio of acid, inthe saliva.
 4. A device of evaluating the risk of caries having such acharacteristic that it is composed of a container for storing the salivacollected from the mouth of the subject, a sensor surface, which comesto contact with the saliva to measure the chemical property of thesaliva, and a computing part for evaluating the risk of possible cariesbased on the measured value for the chemical property of the storedsaliva after a given ratio of acid is dropped in the saliva in thecontainer.
 5. A device of evaluating the risk of caries having such acharacteristic that it is composed of a container for storing the salivacollected from the mouth of the subject, a sensor surface, which comesin contact with the saliva to measure the chemical property of thesaliva, and a computing part for evaluating the risk of possible cariesbased on the difference between the measured value for the chemicalproperty of the stored saliva immediately after the collection and thatafter a given ratio of acid is dropped in.
 6. The device of evaluatingthe risk of caries according to claim 4, further comprising that thecomputing part has a table for storing the relationship, which derivesthe grade of the risk of possible caries from the two measured valuesobtained before and after adding acid to the saliva or the measuredvalue obtained after adding acid in the saliva, between the measuredvalue of chemical property of the saliva and the grade.
 7. A system ofevaluating the risk of caries having such a characteristic that it iscomposed of a measuring device for measuring the chemical property ofthe saliva collected from the mouth of the subject, a server having adatabase storing evaluation criterion data used in evaluating the riskof possible caries based on the measured value for the chemical propertyof the saliva to possess a risk evaluation function for evaluating therisk of possible caries for the subject using the measured value for thechemical property measured by the measuring device, a terminal having atleast an evaluation output function for outputting the result of theevaluation of the risk of the possible caries, and a network forperforming at least one of data inputs/outputs among the measuringdevice, the server, and the terminal.
 8. The system of evaluating therisk of caries according to claim 7, further comprising that thedatabase contains electronic medical chart recording dental conditiontransition data composed of the measured value for the chemical propertyof the saliva of the subject.
 9. The system of evaluating the risk ofcaries according to claim 8, further comprising that the server has anelectronic medical chart browsing function for browsing the dentalcondition transition data of the subject recorded on the medical chartby using the terminal.
 10. The system of evaluating the risk of cariesaccording to claim 8, further comprising that the electronic medicalchart contains the history data of medical treatment of the subjectteeth as dental condition transition data and the server has anevaluation criterion create/update function for creating or changing theevaluation criterion data by taking the statistic on the measured valuedata and the history data recorded on a plurality of electronic medicalcharts.
 11. The system of evaluating the risk of caries according toeither of claim 8 wherein it is composed of a terminal having anindividual evaluation criterion input function for browsing the dentalcondition transition data recorded on the electronic medical chart tocreate or modify the individual evaluation criterion data refined foreach subject.
 12. The system of evaluating the risk of caries accordingto either of claim 7 wherein the database contains the treatmentguideline data giving the guideline for treatment in accordance with theevaluation criteria.
 13. The system of evaluating the risk of cariesaccording to claim 12, further comprising that the server has atreatment recommendation distribution function for distributingappropriate treatment to the individual subjects in accordance with thegrade of evaluation of the risk of possible caries via any of electroniccommunication means such as e-mail.
 14. The system of evaluating therisk of caries according to claim 12, further comprising that thetreatment guideline data contains the subject treatment guideline datafor the subjects and the dentist treatment guideline for the dentists.15. The system of evaluating the risk of caries according to either ofclaim 7 wherein the database contains a mouth condition medicine list.16. The system of evaluating the risk of caries according to either ofclaim 7 wherein the server has an inspection reservation function foraccepting the evaluation of the risk of possible caries by assigning theright of use of the measuring device to the individual subjects whenaccessed by the subjects via their terminals via the network.
 17. Thesystem of evaluating the risk of caries according to either of claim 7wherein the server has an evaluation distribution function fordistributing grades of evaluation of the risk of possible caries to thesubjects via any of electronic communication means such as e-mail. 18.The system of evaluating the risk of caries according to either of claim7 wherein the server contains a dentist list.
 19. The system ofevaluating the risk of caries according to claim 18, further comprisingthat the server has a treatment reservation function for reserving thetreatment by the dentist, who is included in the dentist list, byaccessing from the subject's terminal via the network.
 20. The system ofevaluating the risk of caries according to either of claim 7 wherein theserver has a regular inspection recommendation function for distributingthe recommendation of regular inspection to the subjects depending ontheir grades of evaluation of the risk of possible caries via any ofelectronic communication means such as e-mail.
 21. A program ofevaluating the risk of caries having such a characteristic that itinvolves a step for obtaining the measured value for the chemicalproperty of the saliva collected form the mouth of the subject, a stepfor referring to the evaluation criterion data in evaluating the risk ofpossible caries based on the measured valued for the chemical propertycontained in the database, and a step for outputting the obtainedmeasured value for the chemical property in the form of the grade ofevaluation of the risk of possible caries based on the evaluationcriterion data, and that these steps are performed by a computer. 22.The program of evaluating the risk of caries according to claim 21,further comprising that it involves a step for storing the dentalcondition transition data of the subject containing the measured valuefor the chemical property in the database as an electronic medicalchart, and that this step is performed by a computer.
 23. A method ofevaluating the risk of caries having such a characteristic that itmeasures the chemical property of the saliva collected from the mouth ofthe subject and outputs the measured value for chemical property in theform of the grade of evaluation of the risk of possible caries of thesubject by referring to the database recording the evaluation criteriondata for evaluating the risk of possible caries in accordance with themeasured value, creates an electronic medical chart recording the dentalcondition transition data containing the measured value for the chemicalproperty of the subject's saliva, and performs at least one of input ofthe measured value for the chemical property, reference to the database,and output of the grade of evaluation of the risk of possible cariesthrough data communications via a network.